Wednesday, June 15, 2005

Race Based Medicine: The FDA is considering approval for a drug designed solely for African-Americans with heart failure. Or, more accurately, a drug marketed solely for African-Americans. The drug is BiDil, a combination of isosorbide and hydralzaine, both of which are already available as cheap generics - albeit as separate pills.

The basis of the drug's claim to improve survival in African-Americans with congestive heart failure is this study from last year. It's important to note what the study did not show. It did not show that the benefits of this therapy was limited to African-Americans. Everyone in the study, whether they took placebo or the drug, was African-American. For all anyone knows it could work equally well in Asians or Caucasians or Hispanics.Even worse, the study was designed to give an inherent advantage to the treatment group over the placebo group, which was, on average, six years older. That might not seem like much of an age difference, but in someone with heart disease, the difference between 59 and 65 can make a world of difference in both survival and quality of life; a point underlined by the fact that more of the placebo group had Class IV heart disease (meaning their symptoms were worse to begin with.) [Note: I am becoming dyslexic. The subjects were controlled for age, but the point about the sicker heart failure categories still holds)

There are other reasons to be suspicious of the study and its findings, as this editorial from the New England Journal pointed out:

NitroMed's race-specific strategy promises another large business benefit. Two years ago, NitroMed obtained a second patent, this one based on the use of the formulation in blacks. This patent, the first ever granted to a preexisting drug for a new, race-specific use, pushes back potential market entry by generic sellers of the fixed-dose combination from 2007 to 2020. Less than a month later, NitroMed went public, raising $66 million (even though isosorbide dinitrate and hydralazine are available separately in generic formulations, making it possible to closely approximate NitroMed's combination at a cost of about 44 cents per dose).

Thus, the emergence of the combination treatment as a race-specific drug was driven in large measure by regulatory and market incentives. It remains unknown whether these two drugs in combination with an ACE inhibitor improve survival among patients with heart failure in general (or among patients in other racial groups) beyond the improvement achieved by ACE inhibition alone. But a treatment for all patients with heart failure, regardless of race, could not have extended NitroMed's intellectual property protection by 13 years.

Take the new medication with a large grain of salt. And if you absolutely must try it, why not use the generic alternatives? It isn't that much harder to take two pills instead of one.